Conventionally, a communication control apparatus is proposed in a network communication system, wherein an access request for another device received from a client through a network is received to extract a destination IP address, the IP address is registered in a temporary registration IP address table as an IP address of the communication control apparatus, and a copy of a received frame is retransmitted to the network (see Japanese Laid-Open Patent Publication No. 2007-336401). Also proposed is a network access control method, wherein a proxy request apparatus receives a request of an access request apparatus to make a request to an authentication processing apparatus based on authentication data of the proxy request apparatus, and the authentication processing apparatus receives the request to distribute access control data based on an authentication processing result to an access control apparatus (see International Publication No. WO 2007/138663).